That makes Federer the most efficient Number #1 in Open Era history. The least amount of Number 1 streaks for the most number of weeks.

Indeed. Fun statistic

Federer is also the #1 with highest average points margin to #2 (and #3, #4 etc.) measured in % (since ranking systems differ). I haven't done up the numbers, though. A project I have been thinking of but hasn't got around to yet.